1. Field
Example embodiments relate to semiconductor devices and methods of manufacturing the semiconductor devices. Also, example embodiments relate to semiconductor devices and methods of manufacturing the semiconductor devices in which short-circuits caused by contact bowing may be reduced and/or prevented.
2. Description of Related Art
Generally, a metal contact acts as a conductive line that electrically connects an adhesion region to metal wires or a lower conductive layer to upper metal wires during a multilayered metal wiring process for wiring semiconductor devices.
But as the area of individual elements is reduced to achieve size reduction and higher integration of the semiconductor devices, the width of contact holes typically is reduced also. Furthermore, as the area of individual elements (for example, capacitors) is reduced, the height of these elements may be increased to improve their performance, thus increasing the thickness of an interlayer insulating film used to insulate the elements. In a process of forming a contact hole to expose a lower conductive layer in a thick interlayer insulating film, a High Aspect Ratio Contact (HARC) hole having a large width may be formed in the interlayer insulating film. When ions are scattered and reflect by a hard mask during plasma etching of the contact hole, a bowing phenomenon may occur in the HARC hole. In the bowing phenomenon, the ions may collide with an upper part of a wall of the contact hole due to the high aspect ratio, which further etches the inside of the contact hole. This bowing enlarges the contact hole so that the width of the contact hole is larger than a desired size.
Therefore, since an interval between the contact holes may be reduced and the width of the contact hole may be enlarged, if the contact holes where the bowing occurs are contiguous to each other, an electrical short-circuit may occur between two adjacent contact holes.